As system speeds increase and designs shrink, circuit designers increasingly must debug signal integrity problems. Debugging common digital problems with a scope article tells how to effectively use your high speed oscilloscope to debug modern digital circuits. The ideal digital signal has fast transitions and only two states: high and low. In the real world, digital signals are much more complex. There are two fundamental sources of signal degradation – timing errors and physical layer issues. The most common issues with regard to the physical layer are amplitude problems, edge aberrations, reflections, crosstalk, and ground bounce. Validating and debugging complex embedded systems requires analyzing digital signals, often in both the digital domain and analog domain.